Electric lamp



Feb. 13, 1934. F, ORN 1,947,243

ELECTRIC LAMP Filed July 11, 1953 .Z XZI ENTUR FRITZ BURN BY g'flwi Es:2; TURKEY Patented Feb. 13, 1934 UNITED sTATEs PATENT OFFICE ELECTRICLAltIP Fritz Born, Berlin-Tempelhof, Germany, assignor to GeneralElectric Company, a corporation of New York Application July 11, 1933,Serial No. 679,978, and

in Germany 3 Claims.

gitudinally of the bulb with a concave reflector or shield disposedunder the minor light sdurce so as to direct the light from said sourceagainst the upper portion of the usual paraboloidal reflector whichredirects the light downward to provide a depressed beam. The majorlight source is preferably disposed at the focal-point of the reflectorto provide a substantially horizontal beam of light for the main drivingbeam.

In lamps of the type described, a small portion of the light rays fromthe minor filament is directed upward in front of the upper edge of thereflector. Although these rays may not generally blind personsapproaching the vehicle, due to their steep upward inclination, yet infoggy weather they will of course be'diffused by the vapor particles,causing a glaring light which is particularly troublesome to the driverof the car equipped with the lamp. One of the features of my inventionis the avoidance of this glare by the provision on the front of the bulbof an opaque screen adapted to intercept the light rays causing theglare. The said screen is made comparatively small so that the maindriving beam is substantially unaffected thereby.

Another feature of my invention is vision of an opening at the front ofthe concave reflector or shield through which light rays pass directlyfrom the minor light source to the ground in front of the vehiclewithout being redirected by the paraboloidal reflector.

Still another feature is the provision of a translucent coating on theupper part of the bulb to modify the light from minor filament. In orderto decrease as much as possible the effect of said coating on the maindriving beam, it is preferably terminated on a line above the axis ofthe Bulb.

In the drawing, Fig. 1 is a side view of a lamp comprising my inventionmounted in a reflector; Fig. 2 isa front view of the lamp; and Fig. 3 isa plan view thereof.

Referring to the drawing, the lamp comprises a base 10 and bulb 11having a major filament 12 and minor filament 13 sealed therein. Saidfilaments 12, 13 are preferably located in the longitudinal axis of thelamp with filament 13 foremost. Filament 12 is mounted on lead wires 14,15 which are mounted in a stem press 16.

Filament 13 is mounted on a lead wire 17 and. on the lead wire 15 whichalso supports a concave the pro- July 28, 1932 reflector or shield 18mounted below said filament 13. The lamp is mounted in a reflector 19 sothat the filament 12 lies at the focal point thereof and the reflector18 is so disposed as to direct all the light from the filament 13towardthe upper half of said reflector 19. A small upwardly extendingtab 20 is formed at the front of the reflector 18 to intercept some ofthe forwardly projected rays without adding too much to the weight ofthe internal structure. However, light rays in the form of a small coneare-di rected from filament 13 -beyondthe upper edge of the reflector 19and tend to blind the driver of the vehicle, particularly in foggyweather. Therefore, I provide on the front of the bulb 11 asegment-shaped screen 21, preferably an opaque coating, with the baseline thereof par allel to, and preferably above, the horizontal placethrough the axis of the lamp. Said screen -21 effectively intercepts theupwardly directed light rays and has substantially no effect on thedriving beam produced by the major filament 12.

A small opening 22 is provided at the front of the reflector 18toallowthe projection of a cone 0 of rays from the filament 13 directly towardthe ground in front of the vehicle without being redirected by thereflector 19.

The upper portion of the bulb 11 may also be provided with a translucentcoating 23, preferably a yellow coating, so as to modify the characterof the light beam and render it more eflicientv in penetrating fog. Thelongitudinal boundaries 24 of the said coating 23 are preferably locatedslightly above the axis of the lamp so as to lessen its effect on thedriving beam produced by filament 12.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. An' electric lamp for vehicles comprising a bulb, a pair of lightsources disposed in the longitudinal axis of said bulb, a concavereflector disposed below the forward light source, and an opaque screenon the upper front portion of said bulb adapted to interceptupwardlydirected rays from said forward light source.

v 2. An electric lamp for vehicles comprising a bulb, a pair of lightsources disposed in the longitudinal axis of said bulb, a concavereflector disposed below the forward light source, an opening at thefront-of said reflector for direct transmission of light raystherethrough, and an opaque screen .on the upper front portion of saidbulb adapted to intercept upwardly directed rays from said forward lightsource.

3. An electric lamp for vehicles comprising a bulb, a pair of lightsources disposed in the longitudinal axis of said bulb, a concavereflector disposed below the forward light source, an opening at thefront of said reflector ,for direct trans mission of light raystherethrough, an opaque screen on the upper front portion of said bulbadapted to intercept upwardly directed rays from said forward lightsource, and a translucent coating on the upper-portion of said bulb, thelongitudinal boundaries of said coating lying slightly above the axis ofsaid lamp.

' FRITZ BORN.

